Vehicles with convertible tops or hardtops are typically configured with doors having frameless window glass which seals directly to the convertible top or to the hardtop. The frameless window glass is moved into the seal, e.g., “tucked into” a sealing interface of the convertible top in a fully closed position to provide a seal to prevent wind noise, ingress of air, dust and rain, and to resist outward pressure of the window due to the pressure differential between the interior vehicle compartment and the outside of the vehicle at high speeds. In existing vehicles, a glass indexing system is provided for the purpose of indexing the glass to a partially lowered position to reduce the pressure build-up in the vehicle and the associated seal release or popping noise which may occur during door opening. However, the existing glass indexing systems are typically configured to initiate glass indexing in response to the door latch “ajar” switch being triggered by door movement, which also triggers the door ajar warning in the driver information display. The door ajar switch is typically actuated after the door is opened from the primary (fully closed), and when the door is between the primary and secondary (door partially opened) latch positions. Because the glass indexing is not initiated until after the door has been opened sufficiently to trigger the “door ajar” switch, the window glass is not indexed until after the door has been partially opened and the door opening movement has caused the non-indexed glass to push against, deform and interfere with the sealing interface. The interference between the non-indexed glass and the sealing interface results in increased door opening efforts, delay in door opening, wear and abrasion of the sealing interface, and seal release noise.